Odor identification in mild cognitive impairment subtypes.

The current study examined odor identification using the Brief Smell Identification Test (BSIT) in mild cognitive impairment (MCI) subtypes (17 "amnestic MCI", 46 "amnestic-plus MCI", and 25 "MCI other"). Performance in participants with MCI was compared to that of participants with Alzheimer's disease (AD, n=44) and healthy elderly (n=21). MCI participants performed worse than controls, but better than those with AD. MCI subtypes did not differ. The magnitude of difference between MCI participants and controls was modest, raising some question of the clinical utility of the BSIT in early detection of MCI and early differential diagnosis.